Blender input and shortcuts error
Just go to File menu in blender > Defaults > Load Factory Settings
This Can Work For You But if This Does Not Works then I have Another Idea for you if you are having windows operating system
you should uninstall blender first then before reinstalling it you should go to your c drive or the drive where your operating system is installed then let us suppose it is in C drive so try searching for blender in your file explorer in the c drive 
now delete all the file relating to blender except your project files
also you should go to c drive > program files > Blender Foundation 


  Delete this folder (Blender Fondation)
  now there should not any system file related to blender and then you should re-install it again
  hope this will work !